On subsequent runs, I open the GUI and go to options / include and attempt to add custom files/folders by clicking 'Add files' or folders; error appears.
Error - Crypt32.dll is not found
On Vista 64-bit.
Additional info: I think I narrowed it down to Ccleaner attempting to use the 64bit system files path instead of 32bit on the second execution.
I determined this by replacing the crypt32.dll in c:\windows\system32 with the 32 bit version. This gets it past the crypt32.dll error but it then errors on a second dll file (msasn1.dll).
I ended up testing this b/c I suspected a virus once I identified crypt32.dll was present but not working correctly.
Also, a reboot resets the process to run and fail as before.